[Jerseygyrl]

Accuracy of kappa / lambda FLC ratio post transplant?

by Jerseygyrl on Wed Feb 18, 2015 9:51 am

A friend of mine had a stem cell transplant at the end of September. She emailed me the other day, saying her bone marrow biopsy done on February 5 shows no myeloma! She had been concerned because 8 weeks out of transplant, her kappa/lambda free light chain (FLC) ratio was greatly elevated.

The PA who did her bone marrow biopsy told her the first 2 to 4 months after the transplant the kappa/lambda will not be correct. She was told that, when they kill everything off with the melphalan, it also kills off the B cells and that is what gives you the kappa/lambda ratio.

If this is correct, I am wondering why do a 100-day post transplant checkup if kappa / lambda will not be correct for 2 to 4 months post transplant? Can someone enlighten me on this please?

[JimNY]

Re: Accuracy of kappa / lambda FLC ratio post transplant?

by JimNY on Thu Feb 19, 2015 2:16 pm

Hi Jerseygyrl,

Haven't see you in the forum for a while. Glad to see you're back.

I think I can give you at least somewhat of an answer to your question.

Free light chains are present in the blood of healthy people as well as people with multiple myeloma. If a person's immune system is healthy and they don't have any myeloma cells in their body, kappa and lambda levels will fall within certain "normal" ranges, as will the kappa-lambda ratio.

If there are myeloma cells in the person's body, however, they will tend to produce excessive amounts of (usually) one of the light chains, either kappa or lambda. So you will see elevated levels of that light chain in the blood, and the kappa-lambda ratio will be out of whack.

Now, when someone is recovering from a stem cell transplant, their immune system isn't yet fully "healthy". The myeloma cells in their body may be practically gone, but the immune system is still kickstarting after the bone marrow was hit hard by the melphalan infusion prior to the reinfusion of stem cells.

So the kappa and lambda free light chain levels will be recovering, sometimes at different rates, causing the kappa-lambda ratio to be somewhat unreliable.

There is one unfortunate exception, however. If the person's myeloma was able to withstand the melphalan treatment and starts to progress, you will start to see increasing levels of the person's "involved" free light chain. That level will go out of the normal range, causing the kappa-lambda ratio to go out of range.

So it's useful to check free light chains after a transplant mainly as an early warning system that the myeloma isn't coming back. If the myeloma isn't coming back, the free light chain levels will be within normal, or near normal, ranges, even if the ratio is out of the normal range. But that will be okay.

But, if you didn't do any free light chain testing, you wouldn't have that early look into whether or not the myeloma is taking hold again after the transplant, which you'll see if one of the light chain levels starts to go above the normal range.

Does that help?

[Concerned Dad]

Re: Accuracy of kappa / lambda FLC ratio post transplant?

by Concerned Dad on Sat Aug 13, 2016 7:36 am

Hi Jersey Girl,

How is your loved one doing after the stem cell transplant? How are their ratio's now after one and half year of transplant? Did they go for tandem or allogeneic transplant after the first autologous transplant?

Thanks in advance,
Concerned Dad